Masrie, B., N. Dechassa, T. Tana, Y. Alemayehu, and B. Abebie. “The Effects of Combined Application of Cattle Manure and NP Fertilizers on Yield and Nutrient Uptake of Potato in North-Eastern Ethiopia”. Journal of Science and Sustainable Development, vol. 3, no. 1, Jan. 2015, pp. 1-23, doi:10.20372/au.jssd.3.1.2015.036.